The Clinical Significance of Extreme Leukocytosis among Newborns: A Retrospective Cohort Study.

Objective: The aim of the study is to examine the clinical significance of extreme leukocytosis (>40,000 cells/µL) at birth among neonates.

Study Design: Data were retrospectively collected on 208 infants with leukocytosis >40,000 cells/µL and on matched normal controls as determined in complete blood counts obtained on the first day of life.

Results: There were no significant group differences in birth weight, Apgar's score, timing of respiratory support, hospitalization in special care units or rehospitalization during the first month of life.